In recent years, with the profusion of wireless telephony systems such as cellular phones and the “Personal Handy-phone System” (referred to below as “PHS”), mobile data terminals have been developed that are smaller in size and lighter in weight than data terminals such as conventional notebook personal computers. Various types of such mobile data terminals have been developed, and are often used as what are known as personal digital assistants (PDA).
Given this state of affairs, information providers (IP) are offering a variety of services, such as various online services, viewing of electronic mail, Internet access, and the like, in addition to ordinary voice and fax/data communications. Along with this diversity of telecommunications services, various types of integrated composite equipment are being offered to accommodate the many different types of telecommunications services available.
Incidentally, the operations of vote communication and electronic mail, or the accessing of image with a Web browser, can vary widely in style, depending on the type of telecommunications service used. However, it is extremely difficult to come up with an integrated composite system that enables all operating styles to accommodate all telecommunications services. Accordingly, integrated composite equipment must be configured such that the operating style favors one telecommunications service over another. However, integrated composite equipment that favors one particular operating style will necessarily exhibit poor operability when used with another style. On the other hand, it is also conceivable that a user might have a plurality of equipment that will be suited to the various operating styles. However, since conventional wireless telecommunications devices, foremost among them being cellular phones and PHS, are provided with a telephone number (identification number for wireless communication) for each piece of equipment, that telephone number becomes fixed for each operating style.
Accordingly, in Japanese Patent Application Laid-Open Publication No. Heisei 10-173799, Japanese Patent Application Laid-Open Publication No. Heisei 11-65725, and Japanese Patent Application Laid-Open Publication No. Heisei 5-347574 is disclosed technologies for rendering wireless communications devices containing a telephone number (ID) attachable to and detachable from mobile terminals.
However, the devices disclosed in these patent gazettes are either such that the part with telecommunications capability basically operating as a wide area wireless modem is attachable to and detachable from the main body, or functions as a pager, so that it only functions as a wireless device of a connected terminal. Therefore, when, for example, a wireless device connected to a terminal uses another terminal to access and process mail, data must be sent and received using a cable between the two terminals, and it was substantially difficult to have the various types of data commonly shared among a plurality of pieces of equipment.